Grinding machine



FIG. 1 is a front view of the grinding machine according to the present invention;

FIG. 2 is a rear, left-side perspective view of the grinding machine of FIG. 1;

FIG. 3 is a rear, right-side perspective view of the grinding machine of FIG. 1;

FIG. 4 is a front, right-side perspective view of the grinding machine of FIG. 1; and,

FIG. 5 is a front, left-side perspective view of the grinding machine of FIG. 1. 

The ornamental design for a grinding machine, as shown and described. 